转载:http://blog.youkuaiyun.com/bruce128/article/details/22098795
小结一下ibatis框架下,传入参数为数组类型或者是List类型的sql写法。特别说明,iterate标签仅支持数组和List类型,如果传入Set,Map或其它集合类型,Ibatis会抛异常。
1.传入数组类型,不需要标明parameterClasss,数组和List类型对象一样都可以用<iterate>标签进行遍历。
< select id= "selectOrgIdByNameStr" resultClass= "Integer" > SELECT id FROM org WHERE name IN <iterate close = ")" open = "(" conjunction= "," > <![CDATA[ #[]# ]]> </iterate> </select >
Java 调用代码(注意空指针问题):
@Override public List<Integer> selectOrgIdByNameStr(String[] orgArchArr) { return baseDao.queryForList( "org.selectOrgIdByNameStr" , orgArchArr, String. class ); }
2.传入List类型,泛型参数是八大基本类。这个时候parameterClass传的是List接口的类路径,而不是List的泛型参数的类路径!
< select id= "searchWaiters" parameterClass= "java.util.List" resultClass= "com.chat.domain.zone.WaiterCgExt" > SELECT * FROM waiter w, org o WHERE o.id = w.org_id AND w.id IN <iterate open = "(" close = ")" conjunction= "," > #wid[]# </iterate> </select >
java调用代码如下,注意空指针问题。
@Override public List<WaiterCgExt> searchWaiters(ModAccManVo vo) { List<Integer> widList = baseDao.queryForList("zone.waiter.searchWaitersId" , vo, Integer. class ); if (CollectionUtils.isEmpty(widList)) { return new ArrayList<WaiterCgExt>(); } return baseDao.queryForList( "zone.waiter.searchWaiters" , widList, WaiterCgExt. class ); }
3.传入的List的元素是复杂的对象类型,类型类型里面包含id属性。同样,parameterClass传入的是List接口的类路径,而不是List的泛型参数的类路径。遍历的时候,用#list[].id#就行了,“.”后面跟上要枚举的属性名称。
< select id= "selectWaitersByOrgList" resultClass= "com.chat.domain.zone.Waiter" parameterClass= "java.util.List" > SELECT id, pin as userName FROM waiter WHERE org_id IN <iterate open = "(" close = ")" conjunction= "," > #list[].id# </iterate> </select >
4.传入的参数是map,map的一个value对象的某个字段是List。这个时候,parameterClass是map,这个时候iterate标签得加一个property属性 ,这个属性指定value对象的List字段的名字。否则ibatis会报“ParameterObject or property was not a Collection, Array or Iterator.”。这种是我遇到的最复杂的情况,这种sql搞定了,其它的sql就不是问题了。
< select id= "query" resultClass= "BopEntityTag" parameterClass= "map" > Select * FROM ***_tag WHERE tag_value != 0 <isNotNull property="q.codeSet" prepend= "AND" > code IN <iterate open = "(" close = ")" conjunction= "," property= "q.codeSet" > #q.codeSet[]# </iterate> </isNotNull> </select >
Java调用如下:
@Override public List<BopEntityTagDO> query(***TagDO query) { Map<String, Object> params = new HashMap<String, Object>(); params.put("q" , query); ...... return queryForList(getStatementName( "query" ), params); }